The present invention relates to accelerometers, in particular to micromechanical accelerometers.
Semiconductor materials such as mono and polycrystalline silicon, and semiconductor mass production fabrication techniques have been used to produce micromechanical accelerometers, as in U.S. Pat. No. 4,483,194. More sophisticated devices employ more advanced technology to yield monolithic micromechanical accelerometers, as in U.S. Pat. Nos. 4,805,456 and 4,851,080.
Advances in micromechanical transducer technology are described in Applicant's co-pending, commonly assigned U.S. patent application Ser. No. 07/372,653 entitled BRIDGE ELECTRODES; U.S. patent application Ser. No. 07/373,032 entitled RESTRAINTS FOR MICROMECHANICAL DEVICES; U.S. patent application Ser. No. 07/560,374, filed Jul. 30, 1990, entitled MOTION RESTRAINTS FOR MICROMECHANICAL DEVICES, Issued May 12, 1992 as U.S. Pat. No. 5,111,693; U.S. patent application Ser. No. 07/470,938, filed Jan. 26, 1990, entitled MICROMECHANICAL DEVICE WITH A TRIMMABLE RESONANT FREQUENCY STRUCTURE AND METHOD OF TRIMMING SAME Issued Sep. 1, 1992 as U.S. Pat. No. 5,144,184; and U.S. patent application Ser. No. 07/493,327, filed Mar. 14, 1990 entitled SEMICONDUCTOR CHIP GYROSCOPIC TRANSDUCER Issued May 14, 1991 as U.S. Pat. No. 5,016,172, all of which are incorporated herein by reference.
The present invention is concerned with application of such advances specifically to accelerometers and further advancement of monolithic micromechanical accelerometers.